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Park to Drive Fueling

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Jan. 8, 2015

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This is another tuning article dealing with some of the issues found when running a non-stock intake.

Bogging from N to D generally caused by enrichment commanded by the computer defined in the following tables:
B3629 - Park to Drive Enrichment
B3630 - Park to Drive Enrichment Decay Delay
B3631 – Park to Drive Enrichment Decay Rate
B3651 – Park To drive Decay Factor

My 383 with a marine intake acts great once it’s up to temp, so I didn’t want to totally disable the enrichment.  I just flattened it out under the colder temps it doesn’t do very well with and lowered the highs. Totally disabling them may be best in other applications.

B3629 – Park to Drive Enrichment:
I have no issues once I’m up to running temperature and really don’t want to change anything that already works well.   So this is what my table looked like to start with:

Then what it ended up being after I completed my modifications:

B3630 - Park to Drive Enrichment Decay Delay:


I completely zeroed this table out.

B3631 – Park to Drive Enrichment Decay Rate:

Again I zeroed out this table.

B3651 – Park To drive Decay Factor:


You can 0 this table out. Personally I flat lined it at 0.9648. Theoretically this should give a quick burst of extra fuel and not linger. But you can 0 this too, just make sure to watch your AFR values.

If you’re having issues here, you’re likely having issues starting as well. You might want look into the startup flooding/bogging article as well.